package com.str;

public class str {
  public static void main(String[] args) {
    //
    String s = "iusvhwkdhvisdhvi";
    char[] ar = s.toCharArray();
    for (int j = 0; j < ar.length; j += 2) {
      ar[j] = '@';
    }
    System.out.println(String.valueOf(ar));
  }



}
